The 23-year-old pop star attended the Winter White Gala at London's Kensington Palace wearing an ethereal Reem Acra gown, jewelry from Neil Lane, shoes from Rene Caovilla and a Jenny Packham coat and clutch. The winter wonderland-themed event was hosted by the Centrepoint charity to benefit at-risk homeless youth. Wiliam, the Duke of Cambridge, has been working with Centrepoint since 2005.

"I'm absolutely excited," Swift said of performing at the gala (via the Daily Mail). "I don't think I've ever played at a palace before so it is really wonderful. It's really wondrous, I think they've done an amazing job of putting this together."

Swift, who has become known for her very own dry sense of humor, hobnobbed with William and seemed relieved that the prince also shared her wit.

"I was really happy he was funny," she added.

The recent American Music Award winner performed her hits "I Knew You Were Trouble" and "Fifteen" for the roughly 600 attendees, among them Centrepoint's biggest donors.

"I'm Taylor," she said, addressing the audience. "It is very nice to meet you, especially under these circumstances. It is my first time playing at Kensington Palace, or any other palace for that matter.

"I have to thank you, Prince William, for having me. It's amazing. To call attention to this age group especially, teens and young adults," she added. "It is hard enough being in your late teens to early twenties, then the fact that so many kids have to deal with so much more.

"When I was 15 and I didn't get my way or invited to something or got rejected -- which was a lot -- I used to sit in my room and write songs."

The Grammy winner also performed one of her biggest crossover hits, "Love Story."

"This has reference to palaces, princes and princesses and it is very strange that I end up playing it in a palace," she added.

William chatted up Swift and the evening's other performer, Jon Bon Jovi, who was joined onstage by both Swift and William for their rendition of "Livin' on a Prayer," the Mail reported.

William's wife, Catherine, the Duchess of Cambridge, was not in attendance because she was tending to the couple's 4-month-old son, Prince George.

Meanwhile, William's brother Prince Harry, 29, is gearing up for his own charitable expedition, preparing to participate in the Walking With the Wounded challenge, a 200-mile trek though the Antarctic.

"My father was a little bit concerned, I obviously tried to keep him calm by saying the North Pole was the dangerous one because we were walking on frozen ocean, whereas this time, yes, there's crevasses -- but hopefully the guys will take us around that," Harry said at Base Camp (via the U.K.'s Telegraph). "Apart from frostbite and stuff like that you should be able to look after yourself."

The fourth in line to the throne also made sure to poke fun at his older brother's new dad status.

"My brother, I think he's just quite jealous I managed to get away from a screaming child," he added.

[For the record 3:45 p.m. Nov. 27: An earlier version of this post said Swift's dress was designed by Jenny Packham. The dress was designed by Reem Acra.]